In Reply to: some questions- posted by meretseger on December 19, 2002 at 13:58:05:
the Boids. I would guess that there are other species here and there around the world that also have this feature. I don't know what would cause this, perhaps the durissus group is more primitive than the others. However if this was the case and Crotalus evolved from Agkistodon sp. like some speculate, then I would think Agkistrodon would also possess a rudimentary left lung.